A method of compensating for rotor position error of a rotor of a permanent magnet synchronous generator (PMG) that provides electrical power to a direct current (DC) power generating system, the method including obtaining PMG phase voltages and resolver processed angular position output when the PMG is driven by a prime mover. Once obtained, a PMG fundamental phase voltage waveform is selected by eliminating higher order harmonics. A mechanical angle of the rotor is then converted into an electrical angle, then the electrical angle is aligned within the mechanical angle with a corresponding PMG fundamental phase voltage angle by adjusting offset to the electrical angle. After alignment, a plurality of resolver error offset values associated with the electrical angle are stored and additional values to the compensation table are added by interpolating data between two corresponding resolver error offset values of the plurality of resolver error offset values.

A propulsion system includes an electric propulsor and a gas turbine engine. The propulsion system also includes an electric machine coupled to a rotary component of the gas turbine engine generating a voltage at a baseline voltage magnitude during operation of the gas turbine engine. An electric communication bus is provided electrically connecting the electric machine to the electric propulsor. The propulsion system additionally includes a means for providing a differential voltage to the electric propulsor equal to about twice the baseline voltage magnitude.

A system for providing mechanical and electrical power in a vehicle or other engine-driven platform includes a first engine having a first power rating and a second engine having a second power rating that is less than the first power rating. The system further includes a first generator (for example, an alternator) for generating electrical power for a load operation (such as vehicle propulsion), and a second generator (for example, a DFIG) for generating fixed frequency electrical power; both generators are operatively connected to and powered by the first and/or second engines. The first and/or second engines may be selected to power the first generator for generating power for vehicle propulsion or another load operation depending upon situational power requirements of the engine-driven platform.

A mid-engine extended range electric vehicle includes a vehicle body, a turbo shaft engine, a battery pack, an electric generator, a vehicle control unit, drive motors, a gas controller, a battery controller, a gas storage tank and an intake box. Wherein the vehicle body includes a main body, bottom structure thereof forms frames of the vehicle; the engine is arranged on the frames between front and rear axles and near to the rear axle; an output shaft axis of the engine is located on a symmetry plane of the vehicle body, and an air inlet thereof faces tail of the vehicle; the intake box is communicated with the air inlet and is communicated with intake grilles on a covering piece of the vehicle body via pipelines. The vehicle has features of high effective energy conversion, good operating performance, long endurance mileage and high strength body.

A propulsion system includes an electric propulsor and a gas turbine engine. The propulsion system also includes an electric machine coupled to a rotary component of the gas turbine engine generating a voltage at a baseline voltage magnitude during operation of the gas turbine engine. An electric communication bus is provided electrically connecting the electric machine to the electric propulsor. The propulsion system additionally includes a means for providing a differential voltage to the electric propulsor equal to about twice the baseline voltage magnitude.

A drive system includes an engine, an alternator coupled to the engine, the alternator being configured to power at least one auxiliary load, a traction motor system operatively coupled to drive wheels of the vehicle, the traction motor system being configured for receiving primary electrical power from the alternator and for propelling the vehicle in response to the primary electrical power, and a motor electrically connected to the traction motor system and mechanically coupled to the engine. The motor is configured to receive electrical power from the traction motor system in a dynamic braking mode of operation of the traction motor system and to communicate power to the engine during the dynamic braking mode.

A method of compensating for rotor position error of a rotor of a permanent magnet synchronous generator (PMG) that provides electrical power to a direct current (DC) power generating system, the method including obtaining PMG phase voltages and resolver processed angular position output when the PMG is driven by a prime mover. Once obtained, a PMG fundamental phase voltage waveform is selected by eliminating higher order harmonics. A mechanical angle of the rotor is then converted into an electrical angle, then the electrical angle is aligned within the mechanical angle with a corresponding PMG fundamental phase voltage angle by adjusting offset to the electrical angle. After alignment, a plurality of resolver error offset values associated with the electrical angle are stored and additional values to the compensation table are added by interpolating data between two corresponding resolver error offset values of the plurality of resolver error offset values.

Disclosed is a self-powered vehicle utilized in the field of agriculture, property maintenance, landscaping for use with estate or condominium ground maintenance. It is used for spraying pesticides, herbicides, fertilizer and the like and also for application of similar products in granular form, but further serves as a maintenance platform around a larger industrial facility. Its main payload area is also used for cargo and product transport. It offers high mobility and maneuverability. It is powered with gearhead motors connected to its drive wheels with batteries as its power source. They are charged by an engine driven generator all of which is mounted on the vehicle. Directional control is achieved by the use of a motorcycle handle bar in combination with rotary potentiometers. Each potentiometer controls pulse width of a pulse width modulator thereby controlling the speed of a gearhead motor. The vehicle is optionally a walk behind device but may be provided with a seat behind the handle bar.